animal social behaviour

Although
polygamy also involves mating with multiple partners, it often refers to cases in which individuals form relatively stable associations with two or more mates. Most such species exhibit polygyny, in which males have multiple partners. Some examples include the red-winged blackbird (
Agelaius phoeniceus) and house wren (
Troglodytes aedon) in North America and the great reed...

...territories encompassing the smaller territories of their male mates. The distribution of these mating systems varies considerably among groups. For example, although social monogamy is common and
polygamy rare in birds, the converse is true in mammals; a large fraction of mammals are polygamous. Only a handful of mammal species, including most human societies, are socially monogamous.

galliforms

Gallinaceous birds vary considerably in reproductive behaviour: some exhibit monogamous pair formation with a pair bond lasting through the breeding season, while others show varying types of
polygamy, usually with members of both sexes being more or less promiscuous. Many, if not most, quail and partridge are monogamous, as are ptarmigan, guinea fowl, the hoatzin, some pheasant, and those...

mating system

...to the females, as it is in most birds. In most mammals, however, polygyny is the dominant mating system because the male is not needed for parental care. Therefore, monogamy is favoured over
polygamy only when some environmental resource (food, for example) is limited and when the maximum survival of young requires the care of both parents. As in all other aspects of reproductive...